Comparison Guide

Viagra vs Cialis

Both are effective ED medications, but they work differently. This comparison will help you understand the key differences and which might suit you better.

Viagra (Sildenafil)
  • Lasts 4-6 hours
  • Available without prescription (50mg)
  • Take on empty stomach for best results
Cialis (Tadalafil)
  • Lasts up to 36 hours
  • Daily dosing option available
  • Can take with or without food

Side-by-Side Comparison

FeatureViagraCialis
Active ingredientSildenafilTadalafil
Duration of effect4-6 hoursUp to 36 hours
Time to work30-60 minutes30-60 minutes
Affected by foodYes - fatty foods delay absorptionNo - minimal food effect
Daily dosing optionNoYes (2.5mg or 5mg)
Available without prescriptionYes (50mg Viagra Connect)No - prescription only
Common side effectsHeadache, flushing, visual changesHeadache, back pain, muscle aches
Generic price (approx)£1-3 per tablet£1-4 per tablet

Which Should You Choose?

Viagra May Be Better If...
  • You want to buy over the counter (Viagra Connect 50mg)
  • You're sexually active less than twice per week
  • You prefer a shorter-acting medication that clears your system faster
  • You experience back pain or muscle aches with Cialis
  • You're trying ED medication for the first time
Cialis May Be Better If...
  • You prefer more spontaneity without timing around a pill
  • You're sexually active more than twice per week (consider daily dosing)
  • You want to take it with meals without affecting absorption
  • You experience visual disturbances with Viagra
  • You also have BPH (enlarged prostate) - Cialis is approved for both

Key Differences Explained

Duration: The Biggest Difference

The most significant difference is how long each medication works. Cialis's 36-hour window means you can take it well in advance without worrying about timing, while Viagra requires more planning around sexual activity. For some men, Viagra's shorter duration is actually preferred - the medication leaves your system faster, which can be reassuring.

Food Interactions

Viagra works best on an empty stomach - a heavy meal can delay its effects by up to an hour or more. Cialis isn't significantly affected by food, making it more flexible if you're planning around dinner. This is a practical consideration for many couples.

Daily Dosing

Cialis is the only ED medication with an approved daily dosing regimen. Taking 2.5mg or 5mg daily provides continuous effects, eliminating the need to plan around pills entirely. This can be particularly beneficial for men in regular relationships who want complete spontaneity. Viagra is only taken as-needed.

Side Effects Profile

Both medications have similar overall side effect rates, but the types differ. Viagra is more associated with visual disturbances (blue tinge, light sensitivity) and facial flushing. Cialis is more associated with back pain and muscle aches, typically appearing 12-24 hours after taking it. If you experience bothersome side effects with one, the other may suit you better.

What About Alcohol?

Both Viagra and Cialis can be taken with moderate alcohol (1-2 drinks), but excessive drinking is not recommended with either.

  • • Alcohol can lower blood pressure, increasing side effect risk
  • • Excessive alcohol itself can cause erectile difficulties
  • • Cialis may have a slight advantage as its long duration allows alcohol effects to wear off
  • • Neither medication "cancels out" the effects of alcohol on erections
Important Safety Information

Both Viagra and Cialis have the same core contraindications:

  • Never take with nitrates (for heart/chest pain) - dangerous blood pressure drops
  • Never combine ED medications - don't take Viagra and Cialis together
  • Not suitable for severe heart conditions - consult your doctor first
  • Seek immediate help for erections lasting more than 4 hours, or sudden vision/hearing loss

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Medical Disclaimer

This comparison is for educational purposes only and does not constitute medical advice. The best ED medication for you depends on your individual health profile, lifestyle, and preferences. Always consult a healthcare provider before starting ED medication to ensure it's safe for you.

Last updated: December 2025